Sarcoid arthropathy
Sarcoid arthropathy is the joint, periarticular, and bone manifestation of sarcoidosis, presenting acutely as Lofgren syndrome (bilateral hilar lymphadenopathy, erythema nodosum, and ankle arthritis, 95 percent specific and biopsy-sparing) or as a chronic granulomatous polyarthritis. Acute disease is usually self-limited and treated with an NSAID, while persistent or chronic disease escalates to glucocorticoids, then methotrexate or a tumor necrosis factor inhibitor.
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What this article covers
- Overview
Definition: sarcoid arthropathy is the joint, periarticular, and osseous involvement produced by the noncaseating granulomatous inflammation of sarcoidosis, ranging from an acute, self-limited ankle…
- Epidemiology
Extrapulmonary involvement is common: about 50 percent of patients with sarcoidosis have extrapulmonary disease, and 2 percent have only extrapulmonary disease, of which joint and bone involvement are recognized manifestations.
- Risk factors
Female sex: Lofgren syndrome occurs more often in women.
- Pathophysiology
Noncaseating granulomas are the lesion: aggregates of epithelioid histiocytes without the central caseation necrosis seen in mycobacterial or fungal infection, forming in synovium, periarticular soft…
- Clinical features
Lofgren syndrome (acute): bilateral hilar lymphadenopathy, erythema nodosum (tender, red-brown nodules, classically on the anterior shins), and ankle arthritis, usually accompanied by fever and…
- Differential diagnosis
Reactive arthritis: asymmetric oligoarthritis with conjunctivitis and urethritis following a gastrointestinal or genitourinary infection, associated with human leukocyte antigen B27 (HLA-B27), but…
- Diagnosis
Lofgren syndrome is a clinical diagnosis: when bilateral hilar lymphadenopathy, erythema nodosum, and ankle arthritis are all present, the specificity for sarcoidosis is 95 percent, and biopsy is not required.
- Management
First-line for Lofgren syndrome, an NSAID, since the syndrome is usually self-limited: Naproxen 250 to 500 mg PO twice daily, or Ibuprofen 400 to 800 mg PO three to four times daily (maximum 3200 mg/day).
- Complications
Erosive joint damage and deformity: chronic granulomatous arthritis can progress to erosive damage, deformity, and dactylitis if untreated.
- Prognosis
Lofgren syndrome has an excellent prognosis: the arthritis is usually self-limited and resolves over a short course of weeks, often without needing glucocorticoids.
- Prevention
No primary prevention exists: the trigger for sarcoidosis is unknown, so management focuses on early recognition of Lofgren syndrome to avoid unnecessary biopsy, and on monitoring therapy.
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Related articles
- Sarcoidosis
Sarcoidosis is a multisystem granulomatous disease of unknown cause defined by noncaseating granulomas, most commonly involving the lungs and hilar lymph nodes. Most patients are asymptomatic or have a self-limited course staged by chest radiograph; symptomatic organ-threatening disease is treated with systemic glucocorticoids, with methotrexate or another steroid-sparing agent added for glucocorticoid-refractory or glucocorticoid-intolerant disease.
- Erythema nodosum
Erythema nodosum is a delayed hypersensitivity panniculitis presenting as symmetric, tender, erythematous subcutaneous nodules on the anterior shins, most commonly following streptococcal pharyngitis but also linked to sarcoidosis, inflammatory bowel disease, Coccidioides, Yersinia, pregnancy, and drugs such as oral contraceptives. Diagnosis is clinical, and management is directed at the underlying cause with NSAIDs, bed rest, and cool compresses for symptom control.
- Reactive arthritis
Reactive arthritis is a sterile, human leukocyte antigen B27 (HLA-B27)-associated spondyloarthritis that follows a genitourinary or enteric infection by 1 to 4 weeks, producing asymmetric lower-limb oligoarthritis, enthesitis, and the urethritis-conjunctivitis-arthritis triad. It is a clinical diagnosis of a culture-negative joint. First-line treatment is an NSAID such as piroxicam for at least 2 weeks, escalating to glucocorticoids and then sulfasalazine or a tumor necrosis factor (TNF) inhibitor for disease persisting beyond 3 to 6 months.
- Rheumatoid arthritis
Rheumatoid arthritis is a chronic systemic autoimmune disease causing symmetric small-joint polyarthritis of the hands and feet that spares the distal interphalangeal joints, with morning stiffness over an hour. Diagnosis combines the ACR/EULAR classification criteria with rheumatoid factor, anti-CCP antibody, and radiographs. Treat-to-target management anchors on methotrexate, escalating to a biologic or targeted synthetic disease-modifying antirheumatic drug when remission is not reached.
- Disseminated gonococcal arthritis
Disseminated gonococcal infection is hematogenous spread of Neisseria gonorrhoeae from a mucosal site into the bloodstream, producing either an arthritis-dermatitis triad with usually sterile joint fluid or purulent monoarthritis with a positive culture. Blood, synovial, and mucosal cultures plus nucleic acid amplification testing establish the diagnosis, and treatment is parenteral ceftriaxone with drainage of any purulent joint.